Method and an apparatus for performing an energy efficient desulphurization and decarbonisation of a flue gas

ABSTRACT

A desulphurization and decarbonisation apparatus includes (a) a starter for starting a reaction between an electropositive metal and sulphur oxides and carbon dioxide of a flue gas; (b) a first reaction chamber with a cooling unit for reducing the sulphur oxides and the carbon dioxide of the flue gas in an exothermic reaction with the electropositive metal; (c) a second reaction chamber for generating a first suspension including suspended carbon containing reaction products and sulphur containing reaction products by extracting solid reaction products of the first reaction chamber in a solvent; (d) a third reaction chamber for oxidizing the first suspension to generate a second suspension including suspended carbon containing reaction products and oxidized sulphur containing reaction products; and (e) a separator for separating the oxidized sulphur containing reaction products from the suspended carbon containing reaction products.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. non-provisionalapplication Ser. No. 13/448,645 filed Apr. 17, 2012, and claims thebenefit thereof. The U.S. non-provisional application Ser. No.13/448,645 is incorporated by reference herein in its entirety.

FIELD OF INVENTION

A method and an apparatus for performing an energy efficient combineddesulphurization and decarbonisation of a flue gas comprising sulphuroxides and carbon dioxide are provided.

TECHNICAL BACKGROUND

Carbon-based fossil fuels provide a huge amount of energy, in particularelectrical, thermal or mechanical energy. Along with power generationthe fuel combustion generates various reaction products such as nitrogenoxides, carbon oxides and sulphur oxides. In the past, it was acceptableto allow flue gas discharge from electric utilities and industrialoperations directly into the atmosphere without further treatment of theflue gas. However, with increasing evidence about environmental damagelinked to, for example, the acidification of the atmosphere as a resultof sulphur oxide emissions, and the risk of adverse climate change fromglobal warming due to greenhouse gas emissions, flue gas treatment tomitigate emissions with pollution abatement techniques have become moreimportant to comply to regulations and air quality standards. Currenttechnologies for flue gas treatment involve resource and energyintensive processes.

SUMMARY OF THE INVENTION

Accordingly, there is a need for a method and apparatus which allows acombined energy efficient desulphurization and decarbonisation of fluegas.

A method for performing an energy efficient desulphurization anddecarbonisation of a flue gas comprising sulphur oxides and carbondioxide comprises the steps of:

-   (a) starting a reaction between an electropositive metal and the    sulphur oxides and the carbon dioxide of said flue gas;-   (b) reducing the sulphur oxides and the carbon dioxide of said flue    gas simultaneously in an exothermic reaction with the    electropositive metal and thereby generating reduced gaseous carbon    products and solid reaction products while cooling;-   (c) extracting the solid reaction products of the reducing step (b)    in a solvent to generate a first suspension comprising suspended    carbon containing reaction products and sulphur containing reaction    products;-   (d) oxidizing the first suspension obtained in extracting step (c)    to generate a second suspension comprising suspended carbon    containing reaction products and oxidized sulphur containing    reaction products; and-   (e) separating the oxidized sulphur containing reaction products    from the suspended carbon containing reaction products.

Further, a desulphurization apparatus and/or process chain for use insaid method is provided, said desulphurization apparatus comprising:

-   (a) at least one starter for starting a reaction between an    electropositive metal and the sulphur oxides and the carbon dioxide    of said flue gas;-   (b) at least one reaction chamber (reactor, burner) having cooling    means adapted to reduce the sulphur oxides and the carbon dioxide of    said flue gas in an exothermic reaction with an electropositive    metal;-   (c) at least one reaction chamber adapted to generate a first    suspension comprising suspended carbon containing reaction products    and sulphur containing reaction products by selectively extracting    (dissolving/precipitating) the solid reaction products of reaction    chamber (b) in a solvent;-   (d) at least one reaction chamber adapted to oxidize the first    suspension to generate a second suspension comprising suspended    carbon containing reaction products and oxidized sulphur containing    reaction products; and-   (e) at least one separator adapted to separate the oxidized sulphur    containing reaction products from the suspended carbon containing    reaction products.

In addition, a closed loop desulphurization apparatus for use in saidmethod comprises:

-   (a) at least one starter for starting a reaction between an    electropositive metal and the sulphur oxides and the carbon dioxide    of said flue gas-   (b) at least one reaction chamber (reactor, burner) having cooling    means adapted to reduce the sulphur oxides and the carbon dioxide of    said flue gas in an exothermic reaction with an electropositive    metal;-   (c) at least one reaction chamber adapted to generate a first    suspension comprising suspended carbon containing reaction products    and sulphur containing reaction products by extracting the solid    reaction products of reaction chamber (b) in a solvent;-   (d) at least one reaction chamber adapted to oxidize the first    suspension to generate a second suspension comprising suspended    carbon containing reaction products and oxidized sulphur containing    reaction products;-   (e) at least one separator adapted to separate the oxidized sulphur    containing reaction products from the suspended carbon containing    reaction products; and-   (f) at least one regeneration unit adapted to regenerate the    electropositive metal from the separated suspended carbon containing    reaction products and/or from the separated oxidized sulphur    containing reaction products.

Furthermore, a power plant or a steel plant or a blast furnace or awaste burning plant comprising said desulphurization system or saidclosed loop desulphurization system is provided.

BRIEF DESCRIPTION OF FIGURES

In the following, possible embodiments of the method and apparatus forperforming an energy efficient desulphurization of a flue gas aredescribed with reference to the enclosed figures.

FIG. 1 shows a block diagram of a desulphurization and decarbonisationapparatus for energy efficient desulphurization of a flue gas comprisingsulphur oxides and carbon dioxide according to an example of a possibleembodiment.

FIG. 2 shows a block diagram of a desulphurization and decarbonisationapparatus for energy efficient desulphurization of a flue gas comprisingsulphur oxides and carbon dioxide according to another example of apossible embodiment.

In the figures, reference numerals denote the following components:

-   EPM electropositive metal-   FG flue gas-   1 reaction chamber for starting step (a) and reducing step (b)-   2 reaction chamber for extracting step (c)-   3 reaction chamber for oxidizing step (d)-   4 separator for separating step (e)-   5 anodic oxidation stage-   6 conversion unit-   7 electrolysis unit-   8 burner with igniter-   9 means for bubbling air or oxygen-   10 exit (1) for gaseous product from reaction chamber (b)-   11 exit (2) for gaseous product from reaction chamber (c)-   12 precipitation stage-   13 combined reactor for carrying out extracting step (c), oxidizing    step (d) and separating step (e)-   100 desulphurization and decarbonisation apparatus-   200 regeneration unit-   300 closed loop desulphurization and decarbonisation system

DETAILED DESCRIPTION OF EMBODIMENTS Definitions

An electropositive metal is a metal that is capable of donatingelectrons and usually forms positively charged ions. An electropositivemetal is a metal, whose standard electrode potential with regard to thestandard hydrogen electrode is less than −0.5 V, e.g. metals like zinc,magnesium, lithium.

The first suspension comprising suspended carbon containing reactionproducts and sulphur containing reaction products is a suspensionwherein the solid products from reducing step (a) as well as some excessgases, e.g. carbon dioxide, are extracted with a solvent in extractingstep (b).

Suspended carbon containing reaction products are products obtained inextracting step (c) in a method of an embodiment that contain carbon andare suspended in the solvent.

Sulphur containing reaction products are products obtained in extractingstep (c) in a method of an embodiment that contain sulphur.

The second suspension comprising carbon containing reaction products andoxidized sulphur containing reaction products is a suspension whereinthe first suspension has been oxidized, thereby generating oxidizedsulphur containing reaction products. The carbon containing reactionproducts that are present in the first suspension, in contrast, are notfurther oxidized. The carbon containing reaction products comprised inthe second suspension can be the same as the carbon containing reactionproducts in the first suspension or can be different.

Oxidizes sulphur containing reaction products are products obtainedafter oxidation of the sulphur containing reaction products in oxidizingstep (d) in one embodiment which contain sulphur.

The extraction carried out in extracting step (c) can comprise adissolving or suspending of the reaction products obtained in reducingstep (b) as well as a reaction of these products with the solvent usedin extracting step (c). Further, also a reaction of excess gas fromreducing step (b) with the reaction products in the solvent is possible.

An igniter is a source for starting the exothermic reaction between anelectropositive metal and the sulphur oxides and the carbon dioxide ofsaid flue gas and can include an igniter, an ignition set, a spark plug,etc.

A separator is a separation unit used to separate oxidized sulphurcontaining reaction products from suspended carbon containing reactionproducts.

In one embodiment, a method for performing an energy efficientdesulphurization and decarbonisation of a flue gas comprising sulphuroxides and carbon dioxide is provided, comprising the steps of:

-   (a) starting a reaction between an electropositive metal and the    sulphur oxides and the carbon dioxide of said flue gas;-   (b) reducing the sulphur oxides and the carbon dioxide of said flue    gas simultaneously in an exothermic reaction with the    electropositive metal (EPM) and thereby generating reduced gaseous    carbon products and solid reaction products while cooling;-   (c) extracting the solid reaction products of the reducing step (b)    in a solvent to generate a first suspension comprising suspended    carbon containing reaction products (CCRPs) and sulphur containing    reaction products (SCRPs);-   (d) oxidizing the first suspension obtained in extracting step (c)    to generate a second suspension comprising suspended carbon    containing reaction products and oxidized sulphur containing    reaction products (OSCRPs); and-   (e) separating the oxidized sulphur containing reaction products    from the suspended carbon containing reaction products.

In certain embodiments, the EPM supplied in starting step (a) and/orreducing step (b) can comprise at least one element of the first, secondor third periodic group within the periodic table or zinc. The EPM canin one embodiment comprise at least one metal selected from lithium,sodium, potassium, magnesium, calcium, strontium, barium, aluminum,zinc, or alloys thereof. In a preferred embodiment, the EPC comprises atleast one metal selected from lithium, magnesium, zinc and alloysthereof. In a further preferred embodiment the EPM comprises lithium.When lithium is comprised as EPM, the separation of the CCRPs and OSCRPsis facilitated. In certain embodiments, also combinations of two or moreEPMs can be used.

In certain embodiments, the EPM is added continuously to reducing step(b) after the reaction between the EPM and the sulphur oxides and thecarbon dioxide of said flue gas were started in reaction starting step(a). Furthermore, in certain embodiments, the solid reaction productsare continuously removed from reducing step (b). However, it is alsoprovided that the addition of the EPM and the removal of the solidreaction products is carried out batchwise or semi-continuous.

In certain embodiments, nitrogen oxides that may be present in the fluegas have been separated from the flue gas before introducing it intoreducing step (b). This ensures that no further reaction products areformed in reducing step (b) which could influence the separation of theCCRP and OSCRP in separating step (e). However, it is not excluded inthe method that nitrogen oxides or other low volume by-products, e.g.hydrogen halogenides, water, are comprised in the flue gas, inparticular if the reaction products of the EPM with the nitrogen oxidesor other low volume by-products, e.g. hydrogen halogenides, can easilybe separated from the CCRPs and CSRPs and/or the OSCRPs.

In certain embodiments, the starting step (a) involves starting thereaction between the electropositive metal and the sulphur oxides andcarbon dioxide at a temperature from 200 to 900° C., preferably 400 to900° C. The reaction can thereby for example be started with an igniter,an ignition set or a spark plug, etc., which serves as starter forstarting the reaction in starting step (a).

In certain embodiments, the electropositive metal can be provided insolid or liquid form to the starting step (a) and/or reducing step (b).In preferred embodiments, the electropositive metal is provided inliquid form.

In some embodiments, the electropositive metal can be sprayed into theat least one reaction chamber (b) from an exit of a burner or a nozzleand then get ignited with an igniter in starting step (a). In someembodiments, the starting is carried out near the place where theelectropositive metal is added/injected). The electropositive metal can,in certain embodiments, be preheated before introducing it into the atleast one reaction chamber (b). In certain embodiments, this preheatingis carried out with the thermal energy produced in reducing step (b).

In one embodiment, a temperature during the reduction in reducing step(b) is between 500 and 4000° C., preferably between 1500 and 3000° C.Preferably, the temperature produced in the exothermic reaction duringthe reduction in reducing step (b) is sufficient that it can be used forproducing electrical energy by means of energy conversion. In certainembodiments, the energy conversion can be carried out by heating thecooling means in the at least one reaction chamber (b).

In certain embodiments, thermal energy is provided by the exothermicreaction with said electropositive metal in step (b). This thermalenergy can be used to power a generator being adapted to produceelectricity. For example, the thermal energy can be used in a heatexchanger that in return can power a turbine. In other embodiments, thethermal energy can be used to provide energy (e.g. thermal energy) to agaseous product obtained in reducing step (b) or otherwise present inthe flue gas which then can be used to produce electrical energy, forexample in a gas turbine.

In some embodiments, the thermal energy produced in the reduction inreducing step (b) is used to evaporate a cooling liquid, e.g. water, ina heat exchanger and/or a cooling coil to produce steam. This steam thencan be used in e.g. a turbine to produce electrical energy.

In certain embodiments, cooling is also carried out by other means inthe at least one reaction chamber (b), e.g. by preheating theelectropositive metal provided for starting step (a) and/or reducingstep (b), or by interaction with the walls of the at least one reactionchamber (b).

Preferably, cooling is carried out to a temperature where theintroduction of the solid reaction products generated in reducing step(b) in extracting step (c) does not lead to an evaporation of thesolvent used for extracting these solid reaction products to generate afirst suspension comprising suspended carbon containing reactionproducts and sulphur containing reaction products. In certainembodiments, the cooling is carried out to a temperature at or below theboiling point of this solvent at a certain pressure of the process usedin extracting step (c).

In a certain embodiment, the exothermic reaction in the reducing step(b) is started using the igniter of a burner. However, the starting ofthe reaction can also be carried out using other heat sources. The useof a burner with an igniter is preferred as it can easily provide enoughenergy to start the exothermic reaction. Examples of suitable burnersinclude, but are not limited to oil burners, gas burners, etc.

The at least one starter, e.g. a burner with an igniter (hereinafteralso referred to sometimes as “burner”), for starting the reaction canbe operated at a suitable temperature for starting the reaction of theEPM with the carbon oxides and sulphur oxides contained in the flue gas,e.g. at a temperature between 200 and 900° C., preferably 400 and 900°C. In an exemplary embodiment, the burner can then be operated inreducing step (b) at a temperature between 500 and 4000° C., preferablyat a temperature between 1500 and 3000° C. In certain embodiments, theburning temperature can be controlled in the process. The burningtemperature depends on the reaction conditions, e.g. the content ofcarbon dioxide and/or sulphur oxides in the flue gas, further componentsin the flue gas, the amount of supplied electropositive metal, thecooling means, etc.

In certain embodiments, the burner is operated continuous,semi-continuous or batchwise in reducing step (b), i.e. theelectropositive metal is added continuously, semi-continuously orbatchwise to reducing step (b). A continuous addition of theelectropositive metal is preferred.

During the reducing step (b), reduced gaseous carbon products, such ascarbon monoxide, are formed from the reaction of the EPM with carbondioxide. This gaseous product then can in one embodiment be separatedfrom the further solid products that form by the reducing reaction ofthe EPM, the carbon dioxide and the sulphur oxides, such as sulfides,sulfites, oxides, carbonates, carbides, which form as solids. In certainembodiments, generated carbon monoxide CO can be used as a basis forproducing C₁-materials, such as methanol, syngas, formic acid, etc.

These solids are in certain embodiments cooled when they exit thereaction zone in reducing step (b) and before they are extracted inextracting step (c). This cooling can occur at a wall of a reactionchamber used in reducing step (b) or at the burner used in oneembodiment of reducing step (b) as well as at the further cooling means.In some embodiments, however, an additional cooling step (b′) is carriedout before extracting the solid reaction products of reducing step (b)in extracting step (c). Preferably, the reaction products of reducingstep (b) are cooled to a temperature below the boiling point at thepressure of the process of the solvent used in extracting step (c) sothat no gaseous solvent is produced in extracting step (c).

In the extracting step (c), a first suspension is generated comprisingCCRPs and SCRPs in a solvent. Suitable solvents that can be used inextracting step (c) in embodiments are solvents which can extract thereaction products produced in reducing step (b). In preferableembodiments, the solvent is selected from water and methanol. Inparticular preferred embodiments, the solvent is water. During theextracting step (c), the solvent can suspend or dissolve the reactionproducts of reducing step (b) or react with these reaction products.Therefore, also other products can be formed in the first suspensiongenerated in extracting step (c) besides the CCRPs and the SCRPs. Incertain embodiments, carbides which are formed can react with thesolvent to form acetylene from electropositive metal carbide.

This acetylene then can be separated from the suspension generated inextracting step (c) as a gaseous product and, for example, be used as astarting material for various fine chemicals such as, but not limitedto, 1,4-butanediol and vinyl acetate monomer.

In certain embodiments, also a further gas or liquid can be supplied inextracting step (c) so that during the extraction further products asidefrom the CCRPs and SCRPs can be converted to CCRPs and/or SCRPs. If afurther gas is supplied and also acetylene is formed in certainembodiments, the addition of the further gas has to be carried outseparate from the separation of the acetylene. Preferably the gas isadded after acetylene is separated. In certain embodiments, the furthergas can be carbon dioxide or carbon dioxide with SO_(x). In someembodiments, flue gas or carbon dioxide can be added in extracting step(c) to form further CCRPs and/or SCRPs. Also salt solutions of the EPMcan be added. Further, also excess gas from reducing step (b) can insome embodiments be carried over to extracting step (c) and can bedissolved in the solvent. This dissolved gas then can also react withthe suspended or dissolved solid particles from reducing step (b) and/orgenerated in extracting step (c) through reaction with the solvent toproduce CCRPs and SCRPs. For example, a product formed by the reactionof an electropositive metal carbide with the solvent can be reacted to acarbonate with excess carbon dioxide that is carried over from thereducing step (b).

In certain embodiments, excess gas from reducing step (b) is alsocarried over to extracting step (c) to control the pH in the solvent inextracting step (c). This can then ensure also that the CCRPs and SCRPscan be separated in extracting step (c) and/or oxidizing step (d) and/orseparating step (e).

In certain embodiments, the first suspension generated in extractingstep (c) comprising CCRPs and SCRPs is oxidized in oxidizing step (d) togenerate a second suspension comprising CCRPs and OSCRPs. The oxidationin the oxidizing step (d) can be carried out using known oxidizingagents, such as oxygen or chlorine. In preferred embodiments, oxygen isused in the oxidizing step for the oxidation. This oxygen can beprovided by bubbling air or pure oxygen through the suspension. It isalso possible to spray the suspension in air or oxygen. Preferably, thebubbling is carried out from the bottom of the suspension. In certainembodiments, the SCRPs are oxidized to a sulfate salt of the EPM.

The CCRPs are then, after the oxidizing step (d), separated inseparating step (e) from the OSCRPs in certain embodiments. In certainembodiments, the OSCRPs are essentially all dissolved in the solventafter oxidizing step (d) in separating step (e), and the CCRPs areessentially all precipitated after said step (d). Preferably the OSCRPsare all in solution after the oxidizing step (d) and the CCRPs are allprecipitated after the oxidizing step (d). In certain embodiments, theCCRPs are precipitated as carbonates of the electropositive metal. Incertain embodiments, the OSCRPs are essentially present as dissolvedsulfate salt of the EPM. Preferably the OSCRPs are all present asdissolved sulfate salt of the EPM. In certain embodiments, the OSCRPscan thus be separated from the OCCRPs by way of solid-liquid separation.Generally, this separation is carried out with low energy consumption.In certain embodiments, the energy obtained from the exothermic reactionin reducing step (b) can be used for the separating in separating step(e). In certain embodiments, the energy obtained from the exothermicreaction in reducing step (b) can also be used for providing energy topumps and other equipment, e.g. the regeneration units, of the apparatusand/or closed loop apparatus. Pumps can be used in certain embodimentsto pump the suspensions or solutions produced in the present method aswell as liquid electropositive metal.

In certain embodiments, the suspended carbon containing reactionproducts can already be at least partially separated from the suspensionin extracting step (c) and/or oxidizing step (d). It is also possiblethat all the suspended carbon containing reaction products are separatedin extracting step (c) and/or oxidizing step (d), so that in someembodiments the separating step (e) takes place before or during theoxidizing step (d).

In certain embodiments, the OSCRPs are converted to a not readilysoluble form, e.g. salt, for a subsequent regeneration of theelectropositive metal. In certain embodiments, the not readily solubleform is of certain value and can be further processed. In certainembodiments, the dissolved OSCRPs undergo an anodic oxidation after theseparation in separating step (e) to produce a peroxodisulfate salt ofthe EPM. If the peroxodisulfate salt of the EPM is soluble in thesolvent, the peroxodisulfate anions can in certain embodiments beprecipitated by adding excess potassium chloride and/or ammoniumchloride to form potassium peroxodisulfate and/or ammoniumperoxodisulfate as a precipitate and a mixture of electropositive metalchloride salt and potassium chloride and/or ammonium chloride dissolvedin the solvent. The electropositive metal chloride salt and potassiumchloride and or ammonium chloride can in some embodiments than beobtained as solid product by evaporating the solvent. This evaporationcan in certain embodiments be carried out using the excess thermalenergy or the produced energy produced in the present method, e.g. inreducing step (b) or the separation step (c). In certain embodiments,also energy is obtained by the reaction of the solid reaction productsof reducing step (b) with the solvent in extracting step (c). In certainembodiments, also this energy can be used in the present method forenergy-consuming steps, e.g. the evaporation for obtainingelectropositive metal chloride salt and potassium chloride and orammonium chloride, the electrolysis in the at least one regenerationunit, i.e. the electrochemical regeneration of the electropositivemetal, or pumps.

The produced potassium peroxodisulfate can then be used as a bleachingand/or etching agent. In certain embodiments, further the formedelectropositive metal chloride and potassium chloride and/or ammoniumchloride can, after separation from the potassium peroxodisulfate,undergo a Down's process for the electrochemical regeneration of theelectropositive metal. In this process, electrical energy from renewablepower sources can be used in some embodiments for the regeneration ofthe electropositive metal.

In certain embodiments, the EPM can be regenerated from the carboncontaining reaction products and/or the oxidized sulphur containingreaction products. In such processes, electrical energy from renewablepower sources can be used in some embodiments for the regeneration ofthe electropositive metal. In preferred embodiments, the EPM isregenerated from an electropositive metal carbonate of the CCRPs. Infurther preferred embodiments, the electropositive metal carbonate isconverted by means of aqueous hydrochloric acid into electropositivemetal chloride which is converted by electrolysis into electropositivemetal forming the electropositive metal used in the exothermic reactionwith the flue gas. The chloride generated during the electrolysis canthen be reused for generating the aqueous hydrochloric acid. Also,carbon dioxide produced by the reaction of the carbonate with aqueoushydrochloric acid can be reused or stored. In a possible embodiment theelectropositive metal EPM can be regenerated from reaction products in aclosed loop.

After the regeneration of the EPM after the Down's process after theprecipitation of peroxodisulfate anions and/or after the regenerationfrom the CCRPs and/or the OSCRPs, the regenerated EPM can in someembodiments be reused in the method. For this purpose, the regeneratedEPM can in some embodiments be recycled to the starting step (a) and/orreducing step (b). In preferred embodiments, the EPM is recycled toreducing step (b) when the EPM is added continuously to reducing step(b). In some embodiments, the regenerated EPM can be transported forexothermic reaction with the flue gas in reducing step (b) as a metal insolid form or liquid form or as a hydride in solid form.

Further, a desulphurization and decarbonisation apparatus for use insaid method, is provided, said desulphurization and decarbonisationapparatus comprising:

-   (a) at least one starter for starting a reaction between an    electropositive metal and the sulphur oxides and the carbon dioxide    of said flue gas;-   (b) at least one reaction chamber having cooling means adapted to    reduce the sulphur oxides and the carbon dioxide of said flue gas in    an exothermic reaction with an electropositive metal;-   (c) at least one reaction chamber adapted to generate a first    suspension comprising suspended carbon containing reaction products    and sulphur containing reaction products by extracting the solid    reaction products of reaction chamber (b) in a solvent;-   (d) at least one reaction chamber adapted to oxidize the first    suspension to generate a second suspension comprising suspended    carbon containing reaction products and oxidized sulphur containing    reaction products; and-   (e) a separator adapted to separate the oxidized sulphur containing    reaction products from the carbon containing reaction products.

In certain embodiments, the at least one starter is provided inside thereaction chamber (b).

In certain embodiment the reaction chamber (b) can comprise a burnerwith an igniter or ignition set or spark plug, etc. With this igniter,the exothermic reaction in reducing step (b) can be started in someembodiments in the desulphurization and decarbonisation apparatus, e.g.in a burning chamber, a burning tower or a firing tower used as reactionchamber (b).

In certain embodiments, the reaction chamber (b) in the desulphurizationand decarbonisation apparatus can comprise a burner for the exothermicreaction in the method. This burner is in some embodiments used toinject the electropositive metal into reaction chamber (b).

In certain embodiments, the reaction chamber (c) and/or the reactionchamber (d) and/or the separation unit (e) is a stirred reactor or afluidized bed reactor.

In certain embodiments, reaction chamber (c) and/or reaction chamber (d)can also comprise a separator for separating at least a part of thesuspended carbon containing reaction products. Examples of suitableseparators that can be used as those separators as well as separator (e)include, but are not limited to filters, centrifuges, sedimentationtanks and other separation means for solid-liquid separating known tothe skilled person.

In certain embodiments, the reaction chamber (d) comprises a means forbubbling air or oxygen. In certain embodiments, the reaction chamber (d)comprises means for spraying the first suspension into air or an oxygenatmosphere. In certain embodiments, the reaction chamber (d) comprisesan exit for gas after bubbling or spraying.

In certain embodiments, the reaction chamber (b) and/or the reactionchamber (c) comprise an exit for gaseous products such as carbonmonoxide or acetylene.

In certain embodiments, the reaction chamber (c) and the reactionchamber (d) or the reaction chamber (c), the reaction chamber (d) andthe separator (e) can be combined in one unit, e.g. one vessel, plant,stirrer, tank, caldera, kettle, pot or boiler. This means that theextracting step (c) and the oxidizing step (d) or the extracting step(c), the oxidizing step (d) and the separating step (e) of the methodcan be carried out in one unit. Also the reaction chamber (c) can becombined with the separator (e) and the reaction chamber (d) beseparate, and it is also possible that reaction chamber (c) is separateand reaction chamber (d) is combined with separator (e). Preferably, theextracting step (c), the oxidizing step (d) and the separating step (e)of the method can be carried out in one unit, thus saving equipment costas well as maintenance cost. Further, by combining the three processsteps, also reagent amounts can be reduced, e.g. the solvent.

In certain embodiments, the desulphurization and decarbonisationapparatus and/or a plant comprising said apparatus can further comprisean anodic oxidation stage/unit to produce a peroxodisulfate salt fromthe dissolved OSCRPs provided by said separation unit. In preferredembodiments, the peroxodisulfate salt is precipitated in or after thisstage for separation.

In certain embodiments, the desulphurization and decarbonisationapparatus can further comprise first regenerating means adapted toregenerate the EPM from the separated CCRPs and/or second regeneratingmeans adapted to regenerate the EPM from the separated OSCRPs.

In certain embodiments, the desulphurization and decarbonisationapparatus can comprise means for recycling the regenerated EPM.

In addition, a closed loop desulphurization and decarbonisationapparatus for use in said method is provided, comprising:

-   (a) at least one starter for starting a reaction between an    electropositive metal and the sulphur oxides and the carbon dioxide    of said flue gas;-   (b) at least one reaction chamber having cooling means adapted to    reduce the sulphur oxides and the carbon dioxide of said flue gas in    an exothermic reaction with an electropositive metal;-   (c) at least one reaction chamber adapted to generate a first    suspension comprising suspended carbon containing reaction products    and sulphur containing reaction products by extracting the solid    reaction products of reaction chamber (a) in a solvent;-   (d) at least one reaction chamber adapted to oxidize the first    suspension to generate a second suspension comprising suspended    carbon containing reaction products and oxidized sulphur containing    reaction products;-   (e) at least one separator adapted to separate the oxidized sulphur    containing reaction products from the suspended carbon containing    reaction products; and-   (f) at least one regeneration unit adapted to regenerate the    electropositive metal from the separated carbon containing reaction    products and/or from the separated oxidized sulphur containing    reaction products.

In certain embodiments, the at least one starter is provided inside thereaction chamber (b).

In certain embodiments the reaction chamber (b) can comprise a burnerwith an igniter or ignition set or spark plug. With this igniter, theexothermic reaction in reducing step (b) can be started in someembodiments in the desulphurization and decarbonisation apparatus, e.g.in a burning chamber, a burning tower or a firing tower used as reactionchamber (b).

In certain embodiments, the reaction chamber (b) in the closed loopdesulphurization and decarbonisation apparatus can comprise a burner forthe exothermic reaction in the method. This burner is in someembodiments used to inject the electropositive metal into reactionchamber (b).

In certain embodiments, the reaction chamber (c) and/or the reactionchamber (d) and/or the separator (e) is a stirred reactor or a fluidizedbed reactor.

In certain embodiments, the reaction chamber (d) in the closed loopdesulphurization and decarbonisation apparatus can comprise a means forbubbling air or oxygen. In certain embodiments, the reaction chamber (d)comprises means for spraying the first suspension into air or an oxygenatmosphere. In certain embodiments, the reaction chamber (d) comprisesan exit for gas after bubbling or spraying.

In certain embodiments, the reaction chamber (b) and/or the reactionchamber (c) in the closed loop desulphurization and decarbonisationapparatus further comprise an exit for gaseous products such as carbonmonoxide or acetylene.

In certain embodiments, the reaction chamber (c) and the reactionchamber (d) in the closed loop desulphurization and decarbonisationapparatus or the reaction chamber (c), the reaction chamber (d) and theseparation unit (e) in the closed loop desulphurization anddecarbonisation apparatus are combined in one unit. This means that theextracting step (c) and the oxidizing step (d) or the extracting step(c), the oxidizing step (d) and the separating step (e) of the methodcan be carried out in one vessel. Also the reaction chamber (c) can becombined with the separator (e) and the reaction chamber (d) beseparate, and it is also possible that reaction chamber (c) is separateand reaction chamber (d) is combined with separator (e). Preferably, theextracting step (c), the oxidizing step (d) and the separating step (e)of the method can be carried out in one unit, thus saving equipment costas well as maintenance cost. Further, by combining the three processsteps, also reagent amounts can be reduced, e.g. the solvent.

In certain embodiments, reaction chamber (c) and/or reaction chamber (d)can also comprise a separator for separating at least a part of thesuspended carbon containing reaction products. Examples of suitableseparators that can be used as those separators as well as separator (e)include, but are not limited to filters, centrifuges, sedimentationtanks and other separation means for solid-liquid separating known tothe skilled person.

In certain embodiments, the closed loop desulphurization anddecarbonisation apparatus can further comprise an anodic oxidation stageto produce a peroxodisulfate salt from the dissolved OSCRPs provided inthe separator (e). In preferred embodiments, the peroxodisulfate salt isprecipitated in or after this stage for separation.

In certain embodiments, the closed loop desulphurization anddecarbonisation apparatus can comprise means for recycling theregenerated EPM.

Furthermore, a power plant or a steel plant or a blast furnace or awaste burning plant comprising said desulphurization system or saidclosed loop desulphurization system is provided.

In the present method, apparatus and closed loop apparatus also halogensincluded in the flue gas can also be separated in certain embodiments byforming halogen salts of the electropositive metal. These salts then canbe solid-liquid separated together with the CCRPs and/or OSCRPs and thenbe used for regeneration of the electropositive metal. This isparticularly important when the present method, apparatus or closed loopapparatus is applied to a waste burning plant where higher amounts ofhalogens are produced, e.g. by burning polyvinyl chloride.

In preferred embodiments, the supplied electropositive metal EPM can beformed by lithium metal which reduces carbon dioxide in reducing step(b) after the reaction is started with an igniter in starting step (a)and yields various carbon containing materials. After a preferredhydrolysis in extracting step (c) lithium carbonate is precipitated. Iflithium carbide is formed in reducing step (b) and extracted in water,acetylene can be formed. The produced lithium hydroxide produced in sucha reaction between lithium carbide and water can then react with excesscarbon dioxide transferred from reducing step (b) into the solvent toform lithium carbonate. In such an embodiment, the exit for acetylenehas to be separate from a possible inlet for carbon dioxide. Also,SO_(x) can be contained in the carbon dioxide as it does not affect thereaction. In such preferred embodiments, the lithium metal can alsoreact with the sulphur oxides in the reducing step (b) which can then behydrolyzed in extracting step (c). The sulfur containing reactionproducts of lithium metal can then, in preferred embodiments, beoxidized with oxygen or air comprising oxygen in oxidizing step (d) toproduce dissolved lithium sulfate. Thus, in preferred embodiments, thedissolved lithium sulfate can be separated from the precipitated lithiumcarbonate. In such embodiments, the formed lithium sulfate can befurther oxidized by anodic oxidation to lithium peroxodisulfate. Theperoxodisulfate can in some embodiments than be precipitated with excesspotassium chloride to from potassium peroxodisulfate. The formed lithiumchloride and remaining potassium chloride can in some embodiments bethen, in some embodiments after a precipitation by evaporation of thesolvent, electrolyzed in a Down's process to regenerate lithium, whichcan be recycled to reducing step (b) in a continuous process. Further,in such embodiments, the formed and separated lithium carbonate can bereacted with aqueous hydrochloric acid to form lithium chloride. Thelithium chloride can be electrolyzed to form lithium metal. This lithiummetal can also be recycled to reducing step (b). The chlorine formedduring the electrolysis can be used to produce aqueous hydrochloricacid, which then can be used again for reaction with lithium carbonate.In further embodiments, the lithium carbonate can be used as flux inother processes, as additive for cement and setting accelerator, asadditive in glass ceramics, vitreous enamels, construction industry,aluminum electrolysis, fuel cells, molten carbonate fuel cells, etc.

In the exemplary embodiments the EPM used in starting step (a) andreducing step (b) of a method is lithium metal, and the solvent inextracting step (c) is water.

A first exemplary embodiment, shown in FIG. 1, shows a preferred methodwith four vessels for performing steps (a) to (e).

The reaction chamber 1 of the desulphurization and decarbonisationapparatus 100 is adapted to reduce the sulphur oxides SO_(X) and thecarbon dioxide CO₂ of the supplied flue gas FG in a highly exothermicreaction with lithium. The lithium metal EPM can be directly burned inthe sulphur oxides SO_(x) and carbon dioxide CO₂ of the supplied fluegas FG without a prior separation process. Before the introduction toreaction chamber 1, nitrogen oxides can be, but not necessarily areseparated from the flue gas FG. In the reaction chamber 1, theexothermic reaction can be started using the burner with igniter 8.

In this embodiment, lithium can react with carbon dioxide in reducingstep (b) to reduce it to valuable compounds, e.g. as follows:

2Li+CO₂→Li₂O+CO−314.9 kJ/mol(for comparison: C+O₂→CO₂−393.5 kJ/mol).

4Li+CO₂→Li₂O+C−204.6 kJ/mol.

C+CO₂→2CO+172.5 kJ/mol; CO then could be converted to methanol, formicacid, etc.

2C+2Li→Li₂C₂; Li₂C₂ could then be converted to acetylene.

2CO₂+10Li→Li₂C₂+4Li₂O; Li₂O absorbs excess CO₂.

Li₂CO₃+4C→Li₂C₂+3CO.

Li₂O+CO₂→Li₂CO₃Li₂O+CO₂ at the relevant temperatures around 1500°.

Heat of formation(298K):Li₂O=−597.90 kJ/mol; Li₂CO₃=−1215.87 kJ/mol.

After hydrolysis of these compounds in extracting step (c) in reactionchamber 2, a strongly alkaline Li₂CO₃ suspension can be obtained andsupplied to the oxidizing step (d) in reaction chamber 3 and theseparation step (e) in separator 4. Furthermore, the following reactioncan occur during hydrolysis in reaction chamber 2:

Li₂C₂+H₂O→HC≡CH+2LiOH.

The lithium hydroxide thus formed can be converted to lithium carbonateif an additional gas, such as flue gas, containing carbon dioxide isintroduced in the extracting step (c). Also, excess carbon dioxide fromreaction chamber 2 can be carried over into the solvent in reactionchamber 3 and dissolved therein so that the LiOH, which is also in anequilibrium state with Li₂O, reacts with carbon dioxide to form Li₂CO₃.If further carbon dioxide is added to react with LiOH still present,such addition should be carried out after separating acetylene.

Further, flue gas FG usually contains also oxygen, e.g. 3-4% O₂. Theelectropositive metal Li reacts with O₂ and the resulting Li₂O reactswith CO₂ and forms Li₂CO₃.

Besides the reduction of carbon dioxide, the reduction of sulphur oxidestakes also place in the combustion chamber 1 of the desulphurizationsystem 100. With lithium Li, e.g. the following reactions can takeplace:

6Li+SO₂→Li₂S+2Li₂O.

8Li+SO₃Li₂S+Li₂O.

Li₂O+SO₂Li₂SO₃−438.7 kJ/mol.

Also, these reaction products can be hydrolyzed in extracting step (c)in reaction chamber 2.

Accordingly, a first suspension is generated in reaction chamber 2during the extracting step (c) which comprises CCRPs such as Li₂CO₃ andalso SCRPs and other products such as Li₂S, Li₂SO₃, Li₂SO₅, Li₂S₂O₄,Li₂O, LiOH, etc. as well as some Li₂SO₄. When LiOH and Li₂O are formeddue to the formation of lithiumcarbide in reducing step (b), it ispreferred that those compounds are reacted with carbon dioxide in thefirst suspension to form lithium carbonate. Such a reaction with carbondioxide takes place after the acetylene formed by the reaction oflithium carbide and water is separated. The carbon dioxide in this stepcan be added with SO_(x) which does not influence the reaction. Duringthe extracting step, the SCRPs of lithium all are highly soluble inwater. For example, Li₂S₂O₅ or Li₂SO₃ are highly soluble in water. Onthe other hand, the predominantly produced CCRP lithium carbonate isonly poorly soluble in water and thus leads to the formation of asuspension. The first suspension is submitted to forced oxidation inreaction chamber 3 in oxidizing step (d) by bubbling air or oxygenthrough the suspension, thus forming predominantly Li₂SO₄ as OSCRP,which is soluble at a rate of 350 g/l at room temperature in water andthus is dissolved in water in reaction chamber 3. Lithium carbonate, onthe other hand, will not be further oxidized and forms solid particlesin the suspension as CCRP.

The suspension is then transferred to separator 4. The separator 4 isadapted to separate the OSCRPs, e.g. Li₂SO₄, from the CCRPs, e.g.Li₂CO₃. By having a suspension in water, the sulphur containing reactionproducts of the suspension remain in solution, whereas the carboncontaining reaction products, in particular Li₂CO₃, precipitate with avery low solubility rate of 13 g/l and can be filtered off as a pureproduct for recycling. Along the Li₂CO₃, also other sparingly solublelithium salts like LiOH which contain no sulphur can precipitate incertain amounts. In the separator 4 the precipitated CCRPs, e.g. Li₂CO₃,are filtered from the OSCRPs which are still dissolved in the water. Theseparator 4 outputs an enriched solution which contains the dissolvedlithium sulphur salts, predominantly lithium sulfate (hereinafter calledlithium sulfate solution). In FIG. 1, reaction chamber 1, reactionchamber 2, reaction chamber 3 and separator 4 form the desulphurizationand decarbonisation apparatus 100.

In some cases, at least some of the lithium carbonate or all the lithiumcarbonate can already be separated before or during the oxidizing step(d), so that the separator 4 is combined with reaction chamber 2 and/orreaction chamber 3.

The concentrated lithium sulfate solution can be refined byelectrochemical means to make a regeneration of lithium possible, i.e.the sulfate has to be converted to a not readily soluble form. As shownin FIG. 1 the enriched lithium sulfate solution is supplied to an anodicoxidation stage 5 which produces a peroxodisulfate from the lithiumsulfate solution provided by the separator 4. The anodic oxidation stage5 forms highly soluble Li₂S₂O₈ which is supplied to a followingprecipitation stage 12. In the precipitation stage 12 the peroxidesulfate anions are precipitated by adding potassium chloride KCl in thisexemplary embodiment to form potassium peroxide sulfate K₂S₂O₈ with alow dissolving rate of 50 g/l which precipitates, thus leaving a mixtureof KCl/LiCl behind which can be used for the electrolytic production oflithium metal. In other embodiments, NH₄Cl can be used in place of KCl.

As can be seen in FIG. 1 the KCl/LiCl mixture is supplied to aelectrolysis unit 7 for electrolytic production of lithium metal whereinthe formed lithium chloride and potassium chloride can undergo a Down'sprocess for the electrochemical production of the lithium metal, whichthen can be recycled for reuse in the exothermic reaction with the fluegas FG in reaction chamber 1. The formed potassium peroxide sulfateK₂S₂O₈ can be used as a bleaching agent or as an etching agent, forinstance as an etchant in the electronic industry.

Also the CCRPs separated by the separator 4 can be used for regenerationof the lithium. As can be seen in FIG. 1, the lithium carbonate Li₂CO₃is supplied to a conversion unit 6 where the lithium carbonate isconverted by means of aqueous hydrochloric acid into lithium chlorideLiCl supplied to the electrolysis unit 7. Carbon dioxide, which isproduced in this reaction, can also be reused or stored. Lithiumchloride is converted in the electrolysis unit 7 by electrolysis intolithium metal which then can be recycled for reuse in the exothermicreaction with the flue gas FG in reaction chamber 1. The recycling stepsfrom KCl/LiCl and Li₂CO₃ close the loop for the lithium metal.

As can be seen from FIG. 1 the anodic oxidation stage 5, theprecipitation stage 12 as well as the electrolysis unit 7 formregeneration means adapted to regenerate the lithium, the EPM, from theseparated OSCRPs. Further, the conversion unit 6 as well as theelectrolysis stage 7 form regenerating means adapted to regenerate theEPM lithium from the separated CCRPs. The first regenerating means 6, 7adapted to regenerate the electropositive metal EPM, i.e. lithium, fromthe separated CCRPs, and the second regenerating means 5, 12, 7 adaptedto regenerate the electropositive metal EPM, i.e. lithium from theOSCRPs form a regeneration unit 200 which is adapted to regenerate theelectropositive metal EPM lithium from the separated CCRPs as well asfrom the separated OSCRPs. As can be seen in FIG. 1, thedesulphurization and decarbonisation system 100 and the regenerationunit 200 can form together a closed loop desulphurization anddecarbonisation system 300 for performing an energy efficientdesulphurization and carbon dioxide capture from the flue gas FG,wherein the used EPM lithium is also recycled by means of theregeneration unit 200. This closed loop desulphurization system 300 canbe used for example in a power plant, a steel plant, a blast furnace ora waste burning plant.

FIG. 2 shows another embodiment. As can be seen in FIG. 2, in thisembodiment the reaction chamber 2, the reaction chamber 3 and theseparator 4 are replaced by a combined reactor 13. With this combinedreactor, the extracting step (b), the oxidizing step (c) and theseparating step (d) can be all carried out in one vessel. The furthersteps and components correspond to the steps and components in FIG. 1.It is, however, also possible to only combine two parts of theapparatus, i.e. reaction chamber 2 with separator 4 or reaction chamber2 with reaction chamber 3 or reaction chamber 3 with separator 4, asdescribed above.

In the above exemplary embodiments, the regenerated lithium metal Li canbe transported for the exothermic reaction with the flue gas FG as ametal in solid form or as a liquid or as lithium hydride in solid form.Lithium has a low density and forms a very light material which is evenlighter than water so that it can be easily transported. In a possibleembodiment the regenerated lithium is transported as a metal in solid orliquid form. In an alternative embodiment the lithium is transported aslithium hydride in solid form. Furthermore, the lithium metal Li can bemechanically processed easily because it is relatively soft and can becut with tools. Furthermore, lithium has the advantage that it has oneof the lower melting points among all metals which facilitates theburning of lithium in the reaction chamber 1. In a preferred embodiment,the lithium is sprayed as a liquid into reaction chamber 1 and preheatedprior to the spraying.

The method and system are not restricted to the use of lithium as anelectropositive metal EPM but can use other electropositive metals EPMas well such as sodium, potassium, magnesium, calcium, strontium,barium, aluminum, zinc, or alloys thereof. Preferably used are lithium,magnesium, zinc, and alloys thereof, and lithium is particularlypreferred.

With the present desulphurization and decarbonisation method,desulphurization and decarbonisation apparatus and closed loopdesulphurization and decarbonisation apparatus, the following advantagescan be obtained:

An apparatus is provided that not only produces thermal and electricalenergy but also chemical starting materials which can be used forfurther chemical synthesis processes.

In an apparatus according to embodiments, an electropositive metal EPM,in particular lithium, and its resulting derivatives, can be used forcarbon dioxide capture to produce solid carbonates, in particularLi₂CO₃, and for desulphurization to produce sulphur containing reactionproducts SCRPs, such as Li₂SO₄. The sulphur containing reaction productsSCRPs are enriched as salt in solution, in particular as sulfate saltafter the oxidation. The sulfate salt can be electrochemically convertedto peroxodisulfate anions Si₂O₈ ²⁻. The peroxodisulfate can be used asoxidant, e.g. for etching or bleaching, in the chemical industry. Thecarbon dioxide of the flue gas FG supplied to the reaction chamber (a)can be converted to some extent to carbon monoxide CO and acetylene. Thegenerated carbon monoxide CO can be used as a basis for producingmethanol, syngas, formic acid, etc., whereas acetylene can be used as astarting material for several fine chemicals such as 1,4-butanediol andvinyl acetate monomer. In the system, the SO_(X) separation from theflue gas FG is not necessary since it can be converted by means of theelectropositive metal EPM, particularly lithium, to useful products.

In the apparatus, the desulphurization and carbon dioxide capture can beaccomplished in a single process sequence. The separation of theindividual components/reaction products does not consume additionalenergy as in usual flue gas treatment processes. In particular theseparation of the reaction products makes use of the fact that theoxidized sulphur containing reaction products SCRPs can be dissolved ina solvent, particularly water, whereas the carbon containing reactionproducts do precipitate, thus reducing the energy demand for theseparation to a huge extent.

The system can be used in particular for burning natural gases with highsulphur content. In the reaction chamber (b), a strong exothermicreaction takes place which liberates thermal energy which can exceed500° C., preferably 1500° C. and can, for example, power a steam turbineto generate electricity. Alternatively, the energy produced in thisreaction can be converted by a heat exchanger. This on-site thermalenergy can be used to produce electricity, but also to power on-sitethermal energy intensive processes. The generated heat or steam can alsobe used for other industrial processes, district heating or otherapplications. A further advantage lies in the use of an EPM in themethod, which can be produced from renewable energy sources, thusfurther limiting the energy used in the present method on site. Althoughthe present reducing step (b) in the present method as well as the wholemethod can in principal also be carried out with hydrogen, the use ofthe EPM provides the advantage that it can be easy transported, easilygenerated and does not require expensive equipment, e.g. to preventexplosions or to handle high pressure.

Furthermore, sulphur containing flue gas can generally be fully recycledand cleaned without using any additional carbon based energy for theremoval of the sulphur oxide. In the closed loop desulphurization anddecarbonisation apparatus, further the EPM can be recycled, thuslimiting the need for further EPM and thus saving additional expenses aswell as waste. As the EPM can be produced from renewable energy sources,the present method can be used to convert flue gas into valuableproducts without excessive use of energy on site and rather even canproduce energy during the flue gas treatment.

1. A desulphurization and decarbonisation apparatus, comprising: (a) atleast one starter for starting a reaction between an electropositivemetal and sulphur oxides and carbon dioxide of a flue gas; (b) a firstreaction chamber comprising cooling means for reducing the sulphuroxides and the carbon dioxide of said flue gas in an exothermic reactionwith the electropositive metal; (c) a second reaction chamber forgenerating a first suspension comprising suspended carbon containingreaction products and sulphur containing reaction products by extractingsolid reaction products of the first reaction chamber in a solvent; (d)a third reaction chamber for oxidizing the first suspension to generatea second suspension comprising suspended carbon containing reactionproducts and oxidized sulphur containing reaction products; and (e) atleast one separator for separating the oxidized sulphur containingreaction products from the suspended carbon containing reactionproducts.
 2. The desulphurization and decarbonisation apparatus asclaimed in claim 1, wherein the first reaction chamber (b) comprises aburner.
 3. The desulphurization and decarbonisation apparatus as claimedin claim 1, wherein the second reaction chamber (c) and the thirdreaction chamber (d), or the second reaction chamber (c) and the atleast one separator (e), or the third reaction chamber (d) and the atleast one separator (e), or the second reaction chamber (c), the thirdreaction chamber (d) and the at least one separator (e) are combined inone unit.
 4. The desulphurization and decarbonisation apparatus asclaimed in claim 1, further comprising: an anodic oxidation stage toproduce a peroxodisulfate salt from dissolved oxidized sulphurcontaining reaction products provided by the at least one separator (d).5. The desulphurization and decarbonisation apparatus as claimed inclaim 1, further comprising: first regenerating means for regeneratingthe electropositive metal from the separated suspended carbon containingreaction products, and/or second regenerating means for regenerating theelectropositive metal from the separated oxidized sulphur containingreaction products.
 6. The desulphurization and decarbonisation apparatusas claimed in claim 1, wherein the third reaction chamber (d) comprisesa means for bubbling air or oxygen.
 7. The desulphurization anddecarbonisation apparatus as claimed in claim 1, wherein the firstreaction chamber (b) and/or the second reaction chamber (c) and/or thethird reaction chamber (d) comprise(s) an exit for gaseous products. 8.A closed loop desulphurization and decarbonisation apparatus,comprising: (a) at least one starter for starting a reaction between anelectropositive metal and sulphur oxides and carbon dioxide of a fluegas; (b) a first reaction chamber comprising cooling means for reducingthe sulphur oxides and the carbon dioxide of said flue gas in anexothermic reaction with the electropositive metal; (c) a secondreaction chamber for generating a first suspension comprising suspendedcarbon containing reaction products and sulphur containing reactionproducts by extracting solid reaction products of the first reactionchamber in a solvent; (d) a third reaction chamber for oxidizing thefirst suspension to generate a second suspension comprising suspendedcarbon containing reaction products and oxidized sulphur containingreaction products; (e) at least one separator for separating theoxidized sulphur containing reaction products from the suspended carboncontaining reaction products; and (f) at least one regeneration unit forregenerating the electropositive metal from the separated suspendedcarbon containing reaction products and/or from the separated oxidizedsulphur containing reaction products.